Search results
Results from the WOW.Com Content Network
John Day Fossil Beds National Monument is a U.S. national monument in Wheeler and Grant counties in east-central Oregon.Located within the John Day River basin and managed by the National Park Service, the park is known for its well-preserved layers of fossil plants and mammals that lived in the region between the late Eocene, about 45 million years ago, and the late Miocene, about 5 million ...
The Paleolithic or Palaeolithic (c. 3.3 million – c. 11,700 years ago) (/ ˌ p eɪ l i oʊ ˈ l ɪ θ ɪ k, ˌ p æ l i-/ PAY-lee-oh-LITH-ik, PAL-ee-), also called the Old Stone Age (from Ancient Greek παλαιός (palaiós) 'old' and λίθος (líthos) 'stone'), is a period in human prehistory that is distinguished by the original development of stone tools, and which represents almost ...
In North America, the time encompasses the Paleo-Indian period, which subsequently is divided into more specific time terms, such as Early Lithic stage or Early Paleo-Indians, and Middle Paleo-Indians or Middle Lithic stage. [6] Examples include the Clovis culture and Folsom tradition groups. The Lithic stage was followed by the Archaic stage.
The Lower Paleolithic (or Lower Palaeolithic) is the earliest subdivision of the Paleolithic or Old Stone Age.It spans the time from around 3.3 million years ago when the first evidence for stone tool production and use by hominins appears in the current archaeological record, [1] until around 300,000 years ago, spanning the Oldowan ("mode 1") and Acheulean ("mode 2") lithics industries.
The evolution of life in this time reflected the conditions created by the assembly of Pangaea. The union of most of the continental crust into one landmass reduced the extent of sea coasts. Increased erosion from uplifted continental crust increased the importance of floodplain and delta environments relative to shallow marine environments.
The Precambrian includes approximately 90% of geologic time. It extends from 4.6 billion years ago to the beginning of the Cambrian Period (about 539 Ma).It includes the first three of the four eons of Earth's prehistory (the Hadean, Archean and Proterozoic) and precedes the Phanerozoic eon.
In his 1812 Discours préliminaire to his Recherches sur les ossemens fossiles de quadrupeds put forward a synthesis of this research into the long prehistoric period, and a historical approach to the most recent catastrophe. His historical approach tested empirical claims in the biblical text of Genesis against other ancient writings to pick ...
[43] [44] In central North America, the cooling was by 8.2 ± 3.1 °C over a period of 400,000 years, though there is little indication of significant increase in aridity during this interval. [45] Ice-rafted debris in the Norwegian-Greenland Sea indicated that glaciers had appeared in Greenland by the start of the Oligocene. [46]